D-ring



FIG. 1 is a bottom perspective view of my design for a D-ring;

FIG. 2 is a top perspective view thereof;

FIG. 3 is a bottom view thereof;

FIG. 4 is a top view thereof;

FIG. 5 is a right side view thereof;

FIG. 6 is a left side view thereof;

FIG. 7 is a front view thereof; and,

FIG. 8 is a rear view thereof.

The areas shown in broken lines show environmental structure and form no part of the claimed design. 

CLAIM The ornamental design for a D-ring, as shown and described. 